The joints and muscles of the body function most efficiently when they are in physical balance. Abnormal movements in one line of the body can interfere with proper movements in other joints. For instance, during walking, the foot transfers the weight of the body to the ground and propels the body, which subjects the body to natural forces and postures that can inflict mechanical stress and strain throughout the interrelated chain of joints, ligaments, muscles, and tendons. When foot imbalance is present, there is a negative impact on the feet, legs, hips, back, and cranium.
Imbalance is often caused by excessive pronation of the foot, or “hyperpronation.” Hyperpronation of the foot is the inward, forward and downward twisting of the forefoot relative to the ground. Hyperpronation can cause the framework of the foot to collapse, which can cause plantar fasciitis, heel spurs, tendonitis, bunions, etc., as well as symptoms extrinsic to the foot such as knee pain and low back pain.
To treat and support a hyperpronating foot, foundational stability is provided by maximizing foot-to-ground contact so that the forefoot does not collapse. Traditionally, this is accomplished by using orthotic devices or corrective shoes. In particular, orthotics for supporting a hyperpronating forefoot are designed to support deficits in a foot's contact with the ground, and in essence function so as to build the ground up to the forefoot.
Currently available insoles or orthotics are practical for most closed shoes and for shoes with a lip in the heel that will retain the orthotic within the shoe. During mild and warm weather, many people want to wear open-toed shoes and sandals, and the only option is to glue the orthotic to the shoe permanently. Many people also want to change shoes several times a day, so unless they have orthotics in all of their shoes, they must switch the orthotics from shoe to shoe, which is time consuming and impractical.
Thus, it is desired to have a low-cost orthotic that can be used in a variety of different shoes while providing stabilization to the foot.